Shank.



.H. F. CRAWFORD.

SHANK.

APPLICATION FILED NOV. 14. 1916.

Patented Nov. 6, 1917.

BEST AVAILABLE COP rrr er -rice.

HARVEY F. CRAWFORD, OF BROCKTON, MASSACHUSETTS.

SHAN'K.

To all whom it may concern.-

Be it known that I, HARVEY F. CRAWFORD, a citizen of the United States, residing at Brockton, in the county of Plymouth and State of Massachusetts, have invented certain Improvements in Shanks, of which the following description, in connection with the accompanying drawings, is a specification, like reference characters on the drawings indicating like parts in the severalfigures.

This invention relates to boots and shoes and more particularly to shank stiffening devices for use in the shank portions of boots and shoes.

. In the manufacture of boots and shoes it,

amount of rigidityto the shank of the shoe and provide adequate support for the foot without beingtoo bulky and heavy; Such metallic shank stiffening devices are generally died out from relatively. thin metal sheeting and then temperedor otherwise treated twincrease the rigidity of the metal plate. A serious objection to the use of the metallic shank stiffeners of this type is due to the fact that the relatively thin forward end of the stiffener tends to cut through the outer sole during the continual flexing of the shoe in Wear. W'hile it has. been proposed to provide a curve at the forward end of the shank stiffener corresponding to the reverse curvature of the inner and outer soles at the ball line, this expedient has not been found. entirely satisfactory, particularly since the forward end of the stiffener still, has a tendency to cut into the outer sole when the sole is flexed out "of its normal condition. I

l't is, therefore, an object of the present invention to provide a novel metallic shank stiffener which is so formed and arranged that the forward end of the stiffener is prevented from cutting through the outer sole during the continued flexing of the shoe in the act of walking. To this end the shank stiffening device of the present invention has its forward end formed and arranged to present a cylindraccous bearing portion Specification of Letters Patent.

Patented Nov. 6, 1917.

Application flled November 14, 1916. Serial No. 131,348.

at the forward end of the stiffener in all the positions it assumes relatively to the-outer sole during the wear of the shoe. In the illustrated embodiment of the invention the cylindraceous portion is formed by curling the material at its forward end abruptly downwardly and backwardly in such manner that the diameter of the cylindraceous portion is greater than the thickness of the plate from which the shank stiffener is made. This arrangement provides a substantially blunt bearing for the forward endof the shank stiffener which bearing is maintained during the flexing of'the shoe in wear Whereby the tendency of the forward end of the shank to cut through the outer sole, as with the shank stiffeners now in use, is entirely eliminated.

' Other features and details of construction will be hereinafter more fully described in connection with the accompanying drawings, and the novel features will be set forth in the appended claims.

In the drawings,

Figure 1 shows a preferred embodiment .of the shank stiffener of the present inven-- tion in position on the bottom of a she before the outer sole is applied.

Fig. 2 is a crosssection of the lower rear portion of a shoe illustrating the shank stiffener incorporated therein.

Referring to the drawings, the illustrated shank stiffener 2 comprises a relatively thin piece of sheet metal of a length sufficient to extend from under the heel of the shoe to approximately the ball line and of suitable width to be. located between the inseams along either side of the shank portion of the shoe. This metalstifiener'is arched between its ends to (fOIIOSPOTlfl to the longitudinal arch and also conformed to the transverse conformation of the shank portion of the shoe with which it is intended to be used. In order to give suflicicnt rigidity to the stifl'(mer plate 2 to maintain the arched conformation of the shank portion of the shoe during wear and to provide adequate sup port for the Foot, ribs 4 are formed on the upper surface of the plate, these ribs being preferably parallel to each other and extend ing nearly the entire length of the plate.

In accordance with this invention the for ward end of the stiffener is prevented from cutting through the outersolc, duringthe continual flexing of the shoe in the act of walking, by providing the forward end of tion this is accomplished by abruptly oflset-.

the stifiener with a transversely disposed cylindraceous bearing to engage the upper surface of the outer sole in the different relative positions it assumes on the outer sole. In the illustrated embodiment of the inventing the material across the end of the plate downwardly and then bending or curling it upwardly and backwardly to form a cylindrically shaped portion disposed below the 1 plane of the plate 2 as shown in Fig. 1. This cylindraceous portion may readily be formed at the same time that the plate is pressed into the desired shape and the ribs 4 formed so that there is no appreciable increase in the cost of manufacturing the shank stifienern The diameter of the curl or the cylindrically shaped portion 4, as herein shown, is somewhat greater than the thickness of the plate 2 from which the shank stifi'ener is formed and is preferably approximately the same as the dlstance between the inner-sole and the outer sole of the shoe;

In the embodiment of the invention herein shown and described, the material at the forward end of the stifi'ener plate is abruptly bent downwardly and rearwardly to provide a cylindraceous portion ofiset below the plane of the shank stiffener. It is to be understolld, however, that this showing anddescription are not intended to limit the invention since it is appreciated that the invention is :applicable to use in connection with shank sti eners in which the cylindraceous bearing portion at the forward end of the stiffener differs both as to its relative location above or below the plane of the stifi'ener from the showing in the drawings and from the man ner of providing the cylindraceous bearing portion at the forward end of the stiffener.

To incorporate this shank stiffener in a shoe, the operator {positions the stiifener upon the shank portion of the innersole and secures it by a tack or other fastening means .8 at its rear end in the usual manner, the

forward end of the shank stifiener locating itself a proximately at the ball line of the shoel t will be seen that when the soles of act of-walking, the forward end of the s iank stiffener presents a curved surface at all sEsT AVAILABLE cop ward end of the stiffener from cutting into or otherwise breaking. through the outer sole at this point.

Having described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. As an'article of manufacture, a shank stifiener for boots and shoes comprising a metallic plate of relatively thin material arched between its ends and having its for-; ward end formed and arranged to provide an inte ral cylindraceous bearin across the forwar end of the plate for all t e positions it assumes relatively to the upper side of a shoe sole durin the wear of the shoe.

2. -As an article of manufacture, a shank stiffener for boots and shoes comprising a metallic plate of relatively thin material arched between its ends and having the material at its forward end abru tly curled downwardly out of the plane of t e plate and then rear wardly thereof across the entire width of the plate and constituting a blunt bearing for engagement with the upper side of a shoe sole.

3. As an article of manufacture, a shank stifiener for boots and shoes comprising a metallic plate of relatively thin material arched between its ends and provided at its extreme forward end with an integral cylindrically shaped portion having a greater diameter than the thickness of the plate and constituting a blunt bea'rin for the for ward end of the stiffener in a l the positions it assumes relatively to the upper side of the shoe sole during wear of the shoe.

4. As an article of manufacture, a shank stiffener for boots and shoes comprising a metallic plate of relatively thin material -set from the plane thereof, said cylindraceous bearing having a diameter greater than the thickness of the. plate and presenting at all times a blunt bearing for engagement with the upper side of the sole of a shoe during the continued flexing of the solo in the the shoe are bent atzthe ball line durin the I act of walking.

In testimony whereof I have signed my name to this specification.

A HARVEY F. CRAWFORD. 

